Themes are the fundamental and often universal ideas explored in a literary work.

The Blurred Lines between Human and Beast 

The Island of Dr. Moreau destabilizes one of the major premises of Western civilization: the distinction between humans and animals. In the Judeo-Christian tradition, God placed humans on Earth to rule over the animal kingdom. But the island of Dr. Moreau is populated by “Beast People” exhibiting disturbing combinations of human and animal traits that confound the binary definitions of human and beast. Throughout the novel, the question of who is human and who is an animal is rarely answered clearly. Early on, when Prendick first encounters M’ling and other Beast Folk, he notices their strange anatomy and odd behavior but does not suspect they are not human. Later, Prendick comes to sympathize with the Beast Folk, recognizing that despite their grotesque features and simple minds, they share in most aspects of the human condition. They are capable of loyalty and subterfuge, kindness and violence, great intelligence and comical stupidity, much like their human counterparts.  

In many ways, the imperfections of the Beast People reflect those of the novel’s human characters. The Beast People are upwardly striving beings who actively repress their animal instincts and aspire to act like “men.” The incantations of the Law require them to renounce animal behaviors such as hunting and walking on all fours, but their animal instincts inevitably overpower their moral code. The novel’s human characters are hardly better masters of their animal natures. When faced with starvation, Prendick’s fellow survivors from the Lady Vain fight to the death, ultimately killing each other. Dr. Moreau, despite being a world-renowned scientist, treats animals and Beast Folks inhumanely, ruthlessly inflicting pain and death on the subjects of his experiments. Even Prendick, a paragon of civilized virtue, finds himself capable of cunning and violence when his survival depends on it. Such moral failings on the part of Beast People and actual people suggest that humans are, in many respects, slaves to their animal natures.  

The Frightening Amorality of Science 

Although Dr. Moreau’s scientific achievements are remarkable, his heartless vivisections and careless disregard for his creations symbolize the frightening consequences of science unrestrained by morality. Unmoved by his subjects’ wails of pain, Moreau argues that his scientific interest in the “plasticity of living forms” justifies his actions, regardless of the suffering he inflicts on other living beings. Moreau’s arguments about the physiology of pain may seem convincing on a rational level, but they are no match for the visceral cries of the puma, the latest victim of his experiments. The puma’s harrowing cries inspire so much terror in Prendick that he flees into the jungle just to escape the sound. The products of Moreau’s experiments also inspire terror. The Beast People appear grotesque, and their animal instincts and brute strength make them a threat to all humans, even Moreau. Moreau’s eventual demise at the hands of the Beast People, his own creations, represents a strong condemnation of Moreau’s belief that science supersedes morality.  

Religion as a Tool of Oppression and Repression 

Although the island lacks churches, temples, and other bastions of organized religion, Moreau’s invention of “the Law” to keep the Beast People at heel casts all forms of religion in a cynical light. When Prendick first meets The Sayer of the Law, he immediately recognizes the absurdity of the Law’s prohibitions, which parody the commandments of real-world religions by requiring the Beast People to abstain from beast-like behaviors such as walking on all fours, scratching the bark off of trees, and hunting. The Beast People, most of whom are incapable of anything beyond the most basic reasoning, uncritically parrot the Law, chanting the phrase “Are we not men?” at the conclusion of each commandment. To Prendick, as well as the reader, it is readily apparent that the Beast People are not in fact men. Rather, Moreau has implanted the Law into their minds in order to repress their animal instincts, especially any violent tendencies that might threaten his rule on the island.  

Much like the devout followers of any religion, the Beast People frequently fall short of the commands of the Law, failing to repress their animal instincts and committing the equivalent of sins against Moreau’s Law. But these failures do not detract from the effectiveness of the Law as a tool for controlling the Beast People. Much like a fire-and-brimstone preacher, Moreau threatens the Beast People with physical torture as punishment for deviating from the Law. Moreau’s occasional shows of force strike fear in the hearts of the Beast People, causing them to repress any inclination to rebel. Only the arrival of Prendick on the island seems to shake their faith, when some of the Beast People realize that Prendick, a man like Moreau, lacks Moreau’s supposed omnipotence and omniscience. But after Moreau’s death, Prendick cunningly claims that Moreau has simply left his body and gone to the sky, from where he can watch over the Beast People and punish those who break the Law. Most of the Beast People instantly accept Prendick’s lie, which parodies the biblical story of Christ’s ascension to heaven. The unequivocal falsehood of Moreau’s ascension illustrates the psychological terror he inflicts on the Beast People even after death, much like that experienced by god-fearing devotees of any religion.